Abstract: Japanese encephalitis virus (JEV) was first detected in Australia in 1995 in the Torres Strait and in 1998 in the Cape York peninsula in northern Queensland. JEV detections were limited to genotype II in northern Queensland and Torres Straits until February 2022, when unexpectedly the virus, genotype IV, was detected in stillborn and mummified piglets in four states across south-eastern Australia, including Queensland. This was a rapid and monumental expansion of the known range of this virus.
Japanese encephalitis is a nationally notified disease in both humans and animals, and a category 1 emergency animal disease (EAD) in Australia. On 28 February 2022 the Consultative Committee for Emergency Animal Diseases met. On 4 March 2022, JEV was declared a Communicable Disease Incident of National Significance. As of September 2022, there have been 30 confirmed human cases, 10 probable or suspected cases, and 6 human deaths across Australia. In Queensland, there have been 2 confirmed cases, 2 probable or suspected cases, and one death attributed to JEV.
JEV infection has been confirmed at over 80 commercial piggeries across the four affected states. Businesses representing about 60% of the Australian pork industry have been impacted by the 2022 JEV outbreak, suffering substantial financial losses with preliminary estimates suggesting that the Australian fresh pork supply could fall between 9% and 18% nationally during the period from August to November 2022.
This presentation will describe the current knowledge about the vector ecology of JEV as it relates to Queensland, Australia, including known vector and reservoir host species, as well as outlining the national and state vector surveillance and control plans, and particular challenges controlling mosquito vectors within an animal and food production context.
